Type ASSEMBLE
Source Lines : 358
Fixes Applied : 5
Most Recent Version : Tuesday, December 12, 1978
Last Fix ID : [R13219DS]
Module
DMSITE
Function
TO HANDLE EXTERNAL INTERRUPTS.
Attributes
NUCLEUS, REENTRANT
Operation
DMSITE USES THE WORKAREA EXISECT IN THE NUCLEUS IN
ORDER TO MAINTAIN REENTRANCY.
AN EXTERNAL INTERRUPTION CAUSES CONTROL TO BE PASSED
TO THE EXTERNAL INTERRUPT HANDLER DMSITE. IF THE
INTERRUPT WAS CAUSED BY THE TIMER, BLIP IS ON, AND
THE CONSOLE IS QUIET, DMSITE RESETS THE TIMER TO A
VALUE OF TWO SECONDS, AND TYPES THE BLIP CHARACTER AT
THE TERMINAL. THE STANDARD BLIP CHARACTER IS UPPER
CASE, FOLLOWED BY LOWER CASE (IT MOVES THE TYPEBALL
WITHOUT PRINTING).
IF THE INTERRUPT WAS NOT A TIMER INTERRUPT AND
EXTERNAL INTERRUPT HANDLING IS NOT WANTED, CONTROL
RETURNS TO THE CALLER. IF EXTERNAL INTERRUPT
HANDLING IS WANTED, FREE STORAGE IS OBTAINED TO SAVE
REGISTERS, THE NEW EXTERNAL PSW IS LOADED. ON
RETURN, THE REGISTERS ARE RESTORED AND THE STORAGE
AREA RETURNED. IF THE OLD PSW WAS NOT IN WAIT, THE
OLD EXTERNAL PSW IS LOADED AND CONTROL RETURNED. IF
IT WAS IN WAIT AND THE INTERRUPT CODE WAS NOT AN I/O
INTERRUPT, THE RETURN ADDRESS IS SET AS ADDRESS IN
EXTERNAL OLD PSW AND CONTROL IS RETURNED TO CALLER.
Calls to Other Routines
FREE, FRET, CONWRITE